Gareth Long - 2022-11-22

Hi!

Thought I’d start in the discussion forum first, as I’m not sure of the history of what’s going on, so didn’t want to file a bug report.

The DNS response header ‘Z’ field can be non-zero. This chokes clients that expect these three bits to be zero and faults if they are not - examples include any Zephyr OS-based devices or the Intel-sourced DNS code derived from this.

From the source code, it looks like two bits are defined for reasons, and one is specifically assigned a value, the others aren’t.

Is there a purpose or a plan? Either way, at the moment, it breaks some clients.

Thanks,

Gareth